// Create returns a new SSA Program. An SSA Package is created for
// each transitively error-free package of iprog.
//
// Code for bodies of functions is not built until Build() is called
// on the result.
//
// mode controls diagnostics and checking during SSA construction.
//
func Create(iprog *loader.Program, mode BuilderMode) *Program {
prog := &Program{
Fset: iprog.Fset,
PackagesByPath: make(map[string]*Package),
PackagesByName: make(map[string]*Package),
imported: make(map[string]*Package),
packages: make(map[*types.Package]*Package),
thunks: make(map[selectionKey]*Function),
bounds: make(map[*types.Func]*Function),
mode: mode,
}
h := typeutil.MakeHasher() // protected by methodsMu, in effect
prog.methodSets.SetHasher(h)
prog.canon.SetHasher(h)
for _, info := range iprog.AllPackages {
// TODO(adonovan): relax this constraint if the
// program contains only "soft" errors.
if info.TransitivelyErrorFree {
prog.CreatePackage(info)
}
}
return prog
}
// Hash functions and equivalence relation:
// hashString computes the FNV hash of s.
func hashString(s string) int {
var h uint32
for i := 0; i < len(s); i++ {
h ^= uint32(s[i])
h *= 16777619
}
return int(h)
}
var (
mu sync.Mutex
hasher = typeutil.MakeHasher()
)
// hashType returns a hash for t such that
// types.Identical(x, y) => hashType(x) == hashType(y).
func hashType(t types.Type) int {
mu.Lock()
h := int(hasher.Hash(t))
mu.Unlock()
return h
}
// usesBuiltinMap returns true if the built-in hash function and
// equivalence relation for type t are consistent with those of the
// interpreter's representation of type t. Such types are: all basic
// types (bool, numbers, string), pointers and channels.